We measured change in sexual practices and the incidence of C. trachomatis (CT) and N. gonorrhoeae (NG) within a prospective cohort of Kenyan MSM taking PrEP in Kenya. Over the one year of study participation, CT and NG were diagnosed in urine at baseline, 6- and 12- months. Multivariable Cox regression identified factors associated with incident infection. Sexual practices were assessed at baseline and every 3 months. We evaluated changes over time and in relation to PrEP adherence via generalized estimating equation analysis. From October 2017—January 2018, 158 participants initiated PrEP, having 10.3% baseline CT/NG prevalence (either or both). The incidence was 17.2 cases per 100 person-years (95% CI 11.7–25.5). Incident CT/NG increased with report of: transactional male sex partner (adjusted Hazard Ratio (aHR) = 2.46, p = 0.016, z = 2.40), regular female sex partner (aHR = 2.22, p = 0.051, z = 1.96), greater social support (highest vs. lowest quartile, aHR = 6.24, p = 0.012, z = 2.51), and CT/NG infection prior to enrollment (aHR = 2.90, p = 0.002, z = 3.03). Multiple sex partners, condomless sex, and transactional sex decreased over time and were not associated with PrEP adherence. Urethral CT/NG incidence remained high and there was no evidence of PrEP-related behavioral change. There is need for ongoing etiologic testing, improved understanding of risk from female sex partners, and development of more effective risk reduction interventions.

我们测量了性行为的变化以及沙眼衣原体(CT) 和淋球菌的发病率(NG) 在肯尼亚接受 PrEP 的肯尼亚 MSM 前瞻性队列中。在参与研究的一年中，在基线、6 个月和 12 个月的尿液中诊断出 CT 和 NG。多变量 Cox 回归确定了与事件感染相关的因素。在基线和每 3 个月评估性行为。我们通过广义估计方程分析评估了随时间的变化以及与 PrEP 依从性相关的变化。从 2017 年 10 月至 2018 年 1 月，158 名参与者启动了 PrEP，基线 CT/NG 患病率（或两者之一）为 10.3%。发病率为每 100 人年 17.2 例（95% CI 11.7-25.5）。事件 CT/NG 随着以下报告的增加而增加：交易性男性性伴侣（调整后的危险比 (aHR) = 2.46，p = 0.016，z = 2.40），常规女性性伴侣（aHR = 2.22，p = 0.051，z = 1.96），更大的社会支持（最高 vs. 最低四分位数，aHR = 6.24，p = 0.012，z = 2.51）和入组前 CT/NG 感染（aHR = 2.90，p = 0.002，z = 3.03）。多个性伴侣、无安全套性行为和性交易随着时间的推移而减少，并且与 PrEP 依从性无关。尿道 CT/NG 发生率仍然很高，没有证据表明 PrEP 相关的行为改变。需要进行持续的病因学检测，提高对女性性伴侣风险的理解，并制定更有效的降低风险干预措施。尿道 CT/NG 发生率仍然很高，没有证据表明 PrEP 相关的行为改变。需要进行持续的病因学检测，提高对女性性伴侣风险的理解，并制定更有效的降低风险干预措施。尿道 CT/NG 发生率仍然很高，没有证据表明 PrEP 相关的行为改变。需要进行持续的病因学检测，提高对女性性伴侣风险的理解，并制定更有效的降低风险干预措施。